A cancer referring to malignant tumors in general presents various pathologic conditions depending upon tissues in which it is formed, genetic factors, environmental factors, and the like, of patients. In treatment of cancers, in general, a therapy that is thought to have the highest efficacy is preferentially selected from chemotherapy, radiation treatment, surgical operation, or the like. In determination of a treatment policy of a cancer, it is extremely important to understand a grade of malignancy of a cancer cell precisely. The grade of malignancy is generally determined by the proliferation potency of cancer cells and the efficacy of chemotherapy or radiation treatment. In cancers having a low grade of malignancy, the proliferation potency is low, and the cancer can be easily removed by surgical excision, or the chemotherapy or radiation treatment is effective, so that the prognosis is good. In cancers having a high grade of malignancy, the proliferation potency is high, and the surgical excision is difficult, or the chemotherapy or radiation treatment is ineffective, so that the prognosis is poor. Cancers having a particularly high grade of malignancy require rapid and exact surgical excision. In such cancers, exact auxiliary treatment (radiation treatment or chemotherapy) is essential. Misjudgement of a grade of malignancy makes it impossible to obtain expected therapeutic effect and causes progression of pathologic conditions, occurrence of serious adverse effect, or recurrence. Actually, in many cases, since there is no effective means for determining a feature of cancer, in particular, a grade of malignancy of cancer, treatment is carried out under wrong treatment policy and effective therapeutic effect cannot be obtained, resulting in the termination of death.
To date, the grade of malignancy of cancers have been tried to be judged (discriminated) by using a maker for pathologic conditions or tumors, employing histopathological examination, and the like. However, a definite judgment method that can be commonly employed in almost all malignant tumors has never been established. Furthermore, in conventional judgment, since two pathologic conditions that have been judged to have the same level of grade of malignancy may have utterly different prognoses, they are desired to be discriminated.
Note here that reports relating to the present invention are listed below.
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